1064nm激光诱导等离子体开关控制355nm脉宽可调输出

为得到脉宽可控的355nm紫外脉冲激光输出,采用1064nm脉冲激光诱导等离子体开关技术,控制355nm激光脉冲宽度,在激光电离Cu小孔内壁表面及空气击穿共同作用下,获得了2.8ns～10ns的脉宽可调输出。讨论了1064nm单脉冲输出能量对脉宽压缩的影响,在无延时情况下得到了脉宽最短达2.8ns的脉冲激光输出。在此基础上,保持1064nm单脉冲输出能量不变,采用延时装置改变两光路间的光程差,以控制等离子体开关相对于355nm激光脉冲的形成时间,最终得到脉宽可调的脉冲激光输出。结果表明,等离子体开关结构简单、操作方便、适用范围广,是一种较好的脉冲整形手段。

Generation of width-tunable 355 nm pulses by adopting 1064 nm laser induced plasma shutter

Pulse-shaping technique has found widespread applications in nonlinear optics and material processing. An experimental research on 1064 nm laser-induced plasma shutter to control the 355 nm pulse width is conducted. The width-tunable 355 nm pulses from 2.8 ns to 10 ns are obtained under the ionization of the Cu pinhole and the atmospheric breakdown. The effects of the 1064 nm pulse output energy on pulse compression are discussed, and the shortest output pulse with a width of 2.8 ns is obtained without delay time between two laser paths. Subsequently, adopting the device for delay-time to vary the optical differences between two paths, we obtain the width-tunable 355 nm laser pulses.